1. Field of the Invention
The present invention relates to an electronic keyboard musical instrument for generating musical tones by vibrating a sound board.
2. Description of the Related Art
Electronic keyboard musical instruments have been improved so as to be capable of reproducing natural musical tones having a spreading feeling as if being produced by acoustic musical instruments but there is still a difference in auditory sense from natural musical tones produced by acoustic musical instruments.
That is because an acoustic musical instrument produces not only musical tones sounded by vibrations of vibrating members such as strings but also sounds of contact between components of the musical instrument caused by operation of an operator such as keys and sounds produced by resonance of the respective components and sound boards in complicated interaction, and those complicated sounds can not be fully expressed by the conventional electronic keyboard musical instruments.
There is known an electronic keyboard musical instrument that produces musical tones corresponding to musical tones of operators or pedals that should be generated according to performance operation and makes the produced musical tones sound from a speaker as performance sounds, but there is a limitation in reproduction of sound in a complicated action environment caused by situations (operating state of keyboard and pedals and their operating timing and so on), which results in insufficient expression.
On the other hand, there is known an electronic keyboard musical instrument having speakers, in which a vibrating device is equipped to a sound board so that musical tones by vibration of the sound board is sounded in addition to the sounding by the speakers (See Japanese Patent Laid-Open Publication No. 7-92967).
However, by the electronic keyboard musical instrument according to Japanese Patent Laid-Open Publication No. 7-92967, sounding by the speakers and driving of the vibrating device are performed based on the same performance information generated according to keying information. Therefore, there is a room for improvement in faithful reproduction of both performance sounds by key depressing sounding like an acoustic piano and a damper sound with a spreading feeling generated by resonance and the like of strings other than the struck string when a damper pedal is operated on.